THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS 25 Birch Street, Cambridge, MA 02138 USA Tel. 617-354-0484 Fax 617-354-0665 http://www.aavso.org * * * AAVSO NEWS FLASH * * * Subject: 2003+17 WZ SGE 2043+41 V516 CYG No. 822 1947+58 V542 CYG 2318+17 IP PEG July 30, 2001 1953+77 AB DRA ---------------------------------------------------------------------------- 2003+17 WZ SAGITTAE The rare outburst of this unique dwarf nova is continuing, with significant superhump activity as observed by several observers. We have created a WZ Sge page on our website that is updated daily. We invite you to visit it at: www.aavso.org/wzsge.stm Here you will find recent WZ Sge data and much more. Several satellites, such as FUSE, HST, and Chandra, are scheduled to observe WZ Sge in the coming days and weeks while it is going through its current rare outburst. With these multiwavelength observations, astronomers hope to study dwarf nova oscillations; monitor the response of the white dwarf to this outburst; study the transition from a disk-dominated to a white-dwarf-dominated system; check the 28-second optical periodicity -- is it due to rotation or non-radial oscillations of the white dwarf, and is it shorter while the white dwarf is hotter? The HST spectrometer will be scheduled to observe WZ Sge on August 4, 2001, but only if the variable star is fainter than magnitude 9.2, for anything brighter may damage the spectrometer. Please monitor WZ Sge closely and submit your observations either through the web or electronically so that we may keep our colleagues informed of its activity. CCD observers are highly recommended to continue monitoring the superhumps, which are prominent in the light curve. ---------------------------------------------------------------------------- 1947+58 V542 CYGNI The dwarf nova type (possible SS CYG subclass) cataclysmic variable V542 CYG is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials JUL 27.2722 <14.2 SXN JUL 29.8500 13.4 DPV JUL 29.0306 13.3 DPV JUL 30.0540 13.4 MGH ---------------------------------------------------------------------------- 1953+77 AB DRACONIS The dwarf nova type (Z CAM subclass) cataclysmic variable AB DRA is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials JUL 28.0082 14.7 JCN JUL 30.0715 12.7 CGF JUL 28.9485 12.7 RMQ JUL 30.2944 12.7 LMK JUL 30.0632 12.50 CCD DRG ---------------------------------------------------------------------------- 2043+41 V516 CYGNI The dwarf nova type (SS CYG subclass) cataclysmic variable V516 CYG is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials JUL 26.0709 <15.2 PYG JUL 29.0375 14.1 RMQ JUL 26.1161 16.18 CCD DRG JUL 30.1172 14.30 CCD DRG JUL 27.2832 <14.2 SXN ---------------------------------------------------------------------------- 2318+17 IP PEGASI The dwarf nova type cataclysmic variable IP PEG is in outburst, as indicated by the following observations: AAVSO Observer AAVSO Observer UT Mag. Initials UT Mag. Initials JUL 28.9791 <15.5 RMQ JUL 30.0890 12.7 SPK JUL 30.0660 13.3 MGH JUL 30.1729 12.5 DPL JUL 30.0806 12.38 CCD DRG ---------------------------------------------------------------------------- We thank the following contributors for the data that they have provided for this News Flash: CGF - G. CHAPLE JR., USA MGH - H. MCGEE, ENGLAND DPL - P. DOMBROWSKI, USA PYG - G. POYNER, ENGLAND DPV - P. DUBOVSKY, SLOVAKIA RMQ - M. RESZELSKI, POLAND DRG - R. DIETHELM, SWITZERLAND SPK - P. SCHMEER, GERMANY JCN - C. JONES, ENGLAND SXN - M. SIMONSEN, USA LMK - M. LINNOLT, USA Please monitor these and other variable stars closely and phone-in, fax, or e-mail your observations to the AAVSO. Good observing! Janet A. Mattei, Director Kerri Malatesta, Technical Assistant ____________________________________________________________________________ Symbols may include: < = fainter than magnitude given (variable not seen) : = uncertain CCDV = Charge-coupled device with (V) filter CCD = Unfiltered Charge-coupled device If you would like to contribute to AAVSO NEWS FLASH, please send observations of unusual variable star activity to: observations@aavso.org Those who wish to subscribe (free of charge) or unsubscribe to NEWS FLASH may do so by visiting the following web page: http://www.aavso.org If you would like data from the AAVSO International Database for research purposes, please send your request to: Janet Mattei, AAVSO Director, at aavso@aavso.org An archive of past issues of the News Flash is available at the following web page: http://www.aavso.org/newsflash/ We look forward to including your observations in future editions of AAVSO NEWS FLASH! ____________________________________________________________________________